add transaction method to store

explorer/explorer.go

@@ -13,6 +13,7 @@ type Store interface {
 	Tip() (types.ChainIndex, error)
 	BlockByID(id types.BlockID) (types.Block, error)
 	BlockByHeight(height uint64) (types.Block, error)
+	Transaction(id types.TransactionID) (types.Transaction, error)
 }
 
 // Explorer implements a Sia explorer.
@@ -39,3 +40,8 @@ func (e *Explorer) BlockByID(id types.BlockID) (types.Block, error) {
 func (e *Explorer) BlockByHeight(height uint64) (types.Block, error) {
 	return e.s.BlockByHeight(height)
 }
+
+// Transaction returns the transaction with the specified ID.
+func (e *Explorer) Transaction(id types.TransactionID) (types.Transaction, error) {
+	return e.s.Transaction(id)
+}

persist/sqlite/query.go

@@ -144,3 +144,14 @@ func (s *Store) BlockByHeight(height uint64) (result types.Block, err error) {
 	result, err = s.BlockByID(bid)
 	return
 }
+
+// Transaction implements explorer.Store.
+func (s *Store) Transaction(id types.TransactionID) (result types.Transaction, err error) {
+	var txnID int64
+	if err = s.queryRow("SELECT id FROM transactions WHERE transaction_id = ?", encode(id)).Scan(&txnID); err != nil {
+		return
+	}
+
+	result, err = s.transactionByID(txnID)
+	return
+}

persist/sqlite/txn.go

@@ -58,6 +58,7 @@ func (s *Store) addTransactions(tx txn, bid types.BlockID, txns []types.Transact
 		if err != nil {
 			return err
 		}
+
 		if _, err := tx.Exec("INSERT INTO block_transactions(block_id, transaction_id, block_order) VALUES (?, ?, ?)", encode(bid), txnID, i); err != nil {
 			return err
 		} else if err := s.addArbitraryData(tx, txnID, txn); err != nil {